Height and thez-statistic: Imagine a class of thirty-three 15-year-old girls with an average height of 62.60 inches. The Centers for Disease Control and Prevention (CDC) indicates that the average height for girls at this age is 63.80 inches, with a standard deviation of 2.66 inches.

Question: You predict that this sample of 15-year-old girls is shorter than the national average height for girls at this age. State the null and research hypotheses, in both words and statistical symbolic notation.